There has been known a tire provided in the tread portion with a plurality of main grooves continuously extending in the tire circumferential direction, and transverse grooves extending in the tire axial direction from the main grooves, and thereby provided with a block pattern. when running on snowy roads, the transverse grooves shear snow blocks compacted thereinto to generate shearing force, and thereby, such tire is provided with on-the-snow performance such as traction or driving performance and braking performance. By increasing the volume of such transverse grooves, the shearing force of the compacted snow blocks is increased, and on-the-snow performance can be improved. At the same time, the transverse grooves increased in the volume tend to generate loud noise (e.g. pumping sound) when contacting with and leaving from road surface. Further, the land regions or blocks are decreased in the rigidity, and as a result, uneven wear such as heel-and-toe wear becomes liable to occur. Thus, noise performance and uneven wear resistance are contradictory to on-the-snow performance, and it was difficult to improve these performances in good balance.
Prior art document: Japanese Patent Application Publication No. 2012-224245